Poster: Molecular & Cellular Plant-Microbe Interactions: MPMI
Fungal transcriptome analysis of the Sclerotinia sclerotiorum and Pisum sativum interaction
M. CHILVERS (1), J. Rojas (1), P. Santos (2), J. Wang (1) (1) Michigan State University, U.S.A.; (2) University of Nevada, U.S.A.
Sclerotinia sclerotiorum is a broad host range necrotrophic pathogen that causes white mold on pea (Pisum sativum). Gene expression profiling during infection has been characterized for S. sclerotiorum on several model plants. However, the S. sclerotiorum-P. sativum interaction is still poorly understood. In this study, fungal transcriptomic data was collected at three time points: 12 h, 24 h, and 48 h post inoculation (hpi), from susceptible and partially resistant pea cultivars inoculated with S. sclerotiorum. As a control, transcriptomic data was also collected from mycelia grown on PDA medium used in the inoculations. Four gene clusters were identified using expression profile analysis, one cluster was exclusively up-regulated on PDA, while the remaining three clusters were either associated with the host or sampling time. Gene ontology enrichment analysis demonstrated that 83% of the up-regulated cluster 1 genes were categorized as oxidoreductases at 12 hpi. Whereas, 43% of the up-regulated cluster 2 genes were involved in hydrolysis and transport functions at 24 and 48 hpi. The temporal gene expression profile change may indicate the lifestyle transition of the pathogen from biotroph to necrotroph. In addition, three out of 486 predicted effector candidate genes were up-regulated in planta at 24 and 48 hpi. The identification of key genes involved in the S. sclerotiorum-P. sativum interaction will facilitate effector assisted breeding for disease management.